Search Engine Marketing (SEM) includes placing a bid on one or more keywords of a search engine to display a hyperlinked advertisement, e.g., to a user of the search engine who submits a query including one of the keywords, when the bid is sufficiently high. Manually managing these keywords can be difficult since advertisers often bid and manage hundreds to thousands of keywords. Automation of SEM management has traditionally included use of mathematical/financial models that determine which individual keywords will maximize click traffic and/or profit margin. Since more than one keyword can represent the same meaning (synonymy) and more than one meaning can be represented by the same keyword (ambiguity), the traditional individual keyword management solution is less than optimal. Therefore, there exists a need for a better to manage keywords for advertisements.